Apexi make a whole range of these products...commonly known as "Sender benders"

No for TPS, but for MAP (manifold absolute pressure) sensors, MAF manifold air flow sensors)

The autospeed website has written some articles on do it your self.

There is also a device called a "Megasquirt" which is a build it yourself EFI unit...you need to know a bit about electronics to get that one up and running though